Internal pipe cutter



July 14, 1931. '6. v. PowERs 1*,)8143058 INTERNAL PIPE CUTTER Filed March 1. 192e 2 shuts-sheet v 1 l# muy,

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INTERNAL PIPE CUTTER Filed March l, 1928 2 Sheets-Sheet 2 drill Patented July 14, 1931 #Ulm'rlazlii STATES PATENT OFFICE @MME V. POWERS, OF OKLAHOIAVCITY, OKLAHOMA, ASSIGNOB.` TO AMERICAN IRON AND MACHINE WORKS COMPANY, Ol' OKLAHOMA CITY, OKLAHOMA, A CORPORATION OF OKLAHOIA appunti ma Ima 1, ma. Lsemi no. saam.

This invention relates to pipe cutters such as are used in connection with oil or other wells, and particularly to a pipe cutter designed to cut rotary drill pipe -while the ipe is in position in a hole being drilled) in order to remove a stringhof rotary drilling tools out of the hole w ich have become stuck therein and which would otherwise be lost.

The general object of the invention is to Aprovide a device of this character which is very simple, eilcient, and which may be dropped down on the inside of the rotary drill pipe by means of a string of tubing or other pipe lengths or tool lengths and by which the string of rotary drill tubing may be cut oil' at any desired point to permit its removal.

A further object is to providea device of this character which, when turned in one direction, will cause pivoted steps to be projected outward to engage against a colar or shoulder on the rotar pipe so as to support the cutting device rom longitudinal movement, and provide means whereby cutters may then be forced outward to bear against the rotary drill pipe and may be rotated to cut away the rotary drill pipe.

Another object is to provide a device of this kind which can also be used for cutting cemented casing above the cement, allowing the casing to be removed after a producing well has ceased to produce.

A still further object is to provide a device of this kind which, slightly modified, may operate in well pipe casings to cut the latter at any desired point.

My invention is illustrated in the accompanying drawings, wherein v Figure 1 is a side elevation of a pipe cutter constructed in accordance with my invention;

Figure 2 is a vertical sectional view thereof with the blades retracted;

Figure 3 is a section on the line 3l-3 of Figure 2; v

Figure 4 is a sectional view on the same plane as Figure 3 but showing a modification;

Figure 5 is a section on the line 5-5 of Fi ure 1; l

igure 6 is a fragmentary longitudinal section of my internal pipe cutter showing the weight equalizing device connected thereto;

Figure 7 is a section on the line 7-7 of Figure 6;

Figure 8 is a fragmentary vertical sectional view of a preferable form of the cutter;

Figure 9 is a section on the line 9-9 of Figure 8;

Figure 10 is a fragmentary elevation of the expanding head showing the slot for one of the cutters;

Figure 11 is an under side plan view of the head shown in Figure 10.

Referring to these drawings, it will be seen that my internal pipe cutter comprises a collar 10 which is shown as having a reduced screw-threaded lower portion 11. Internally, this collar is many-sided in cross section, as at 12. I have shown in Figure 3 that this collar may -have a square passageway extending therethrough but, on the other hand, the collar might be formed circular but with longitudinally extending grooves 13, as shown in Figure 4. Having screw-threaded engagement with this co1- lar 10 is the longitudinally extending pipe section 14 formed with slots 15.

Pivoted upon a pin 16 extending transversely across this pi e section arethe two cutters 17 and 18. ach of these cutters is pivoted upon the pin 16 nearer the lower end than the upper and each cutter at its upper end is formed with the outwardly and upwardly projecting cutting blade 19. Each cutter at its lower end is formed to provide a downwardly and outwardly extending portion or jaw 20, and between these jaws is disposed a compression spring 21 which acts to force these jaws outward and thus acts to contract the upper ends of the cutters and draw them inward of the pipe section 14.

The uppler ends of the cutters cross each other, as s own in Figure 2, so as to leave a V-shaped space between the cutters. O rating through the sleeve 10 and having on- -zo l gitudinal movement therein but rotative engagement therewith is a shank 2 2 which fits the collar 10 and this shank at its lower end carries a swiveled head 23 which is formed in its lower face with two upwardly and outwardly extending grooves 24:. When this head 23 is forced downward, the upper ends of the cutters will be received in said grooves and as the head is forced further downward these cutters will be wedged outward until `their cutting edges 19 pass through the slots 15 and engage the pipe section which constitutes the shankof the rotary drilling tool.

While any suitable means maybe used for swivellin the head 23 to the shank 22, I preferably orm the swivel, at least in some cases, as shown in Figure 8 wherein the shank 22 has a reduced portion fitting within the socket 23a formed in the head 23, this reduced portion of the shank having a circumferential groove 23h, the head being provided with a screw engaging in this groove in an obvious and well-known manner. An means for swivelling the head to the shan however, may be used.

The lower end of the pipe section 15 is swiveled at 25 to a supporting section 26 which has a rounded lower endand which is formed with a circumferentially extending groove or recess 27 Pivotally mounted within this recess are the two arcuately curved stops 28. These are pivoted at 29 and have the beveled end faces 30. These stops are tapered from the top of the fulcrum or pivot down to the center, as shown in Fi re 1.

In igure 6, I have illustrated a weight equalizer which is designed to be disposed about two joints above the cutter and which does away with the danger of getting too much weight on the blades and causing them d to stick, this weight equalizer being a necessary part of the cutter for the reasons stated. The weight equalizer comprises a longitudinally extending rod or shaft 31 which is attached to the lower end of a. string of tubing which is keyed to a. collar 32, this shaft or rod being shiftable longitudinally through the collar 32 but in any position rotating with the collar. This collar has a reduced lower portion which is exteriorly screw-threaded for the reception of an outer tube or pipe 33. A shoulder 34`is thus formed at the lower end of the collar 32 and the lower end of the rod or shaft 31 is enlarged, as at 35, to provide a shoulder 36 adapted to coact with the shoulder 34 toA support the string of tools. Thus when the shoulder 36 engages with the shoulder 34:, the tubular member 33 will be supported, but when the tubular member 33 is held from downward movement the shaft or rod 31 may be shifted downward. The lug 37 in the lower' end of the pipe 33 is solid and threaded on one end to fit the pipe 33' and at tHe-other end to lit a two-inch cou ling 37a, which in turn has screw-threade engagement with a ,bushing 22a whereb 1t ma be connected to the member 22. he colliar 32 is preferably about six inches long and the pipe section 33 about twenty inches lon".

When the cutter is let down into the pipe that is to be cut, the shoulder 36 is against the shoulder 34 and the head 35 thus supports the whole weight of the cutter and the allied parts. -When the cutter reaches the seat, that is, when it reaches a point where cutting is to be performed and can go no further downward by reason of the outward movement of the stops 28, the cutter and the two joints of pipe above the cutter stop or are held from any further downward movement. Then the Weight 31 with the head 35 is lowered until the head 35 hits the plug 37, thus putting the weight of all the pipe from this point on up to 'the top of the hole onto the blade opener 23. This positively opens the blades. When the blades have been opened, the rod 31 is lifted upward to about the middle of the pipe section 33 so that all the pipe above the part 32 and connected to the member 31 is hanging from the derrick instead of resting on the cutter blades. This operation leaves only the weight of two joints of pipe and the parts 37, 33 and 32 on the cutter blades so that the cutter blades at this time are submitted to an exact and definite pressure outward against the pipe that is being out and this eliminates the transmission to the cutter of all the up and down movement of the pipe sections above the equalizer which is caused by rotating these plpe sections. This rotational movement is transmitted to the member 31, through the member 31 to the member 32, and so onto the cutter.

When three thousand feet of two-inch applied. All this twist and up and down movement that is caused by friction is not transmitted tothe cutter or allied parts and thus does not affect the position of the cutter which is in the same vertical position at all times.

While in Figure 2 I have illustrated a construction wherein the cutters are forced apart by a spring 21, this is not the preferable construction, andin Figure 8 I illustrate the preferable construction. The head 23-is of the same form as previously described, as are the cutters 17 and 18. The lower ends of the cutters are beveled ofi' at an inclination of approximately 45 in opposite directions, as at 38, so as to bear ISI) against a conical cap 39 which is supported by and ur ed upward by a compression spring 4.0, t iis spring resting upon a nut 41 pinned to a spindle or shaft 42 formed upon the member 2G and constituting means for swivelly connecting the lower portion of the pipe section constituting the cutting mechanism. This connecting spindle 42 passes upward through an annular member previously referred to as 25 which is exteriorly screw-threaded to fit within the casing 14. 'Ihe n'ut 41 is pinned to the stem 42, and disposed between the nut and the neck 25a of the annular member 25 is a, lock washer 43 which is keyed tothe Stem 42 so that it cannot rotate. The stem 42, the lock washer 43 and the nut 41 constitute .the means for swivelly connectingl the lower or anchoring portion of the device to the upper portion thereof.

It will be seen that with this construction pressure on the bottoni of the cap 39 by the spring 40 urges the blades to a closed position and serves to keep these blades 17 and 18 closed. The spring 40 rests on the top of the nut` 41 that holds the swivel connection together and it is the friction of this spring bearing upon this nut and bearing upon the washer 43 that keeps the supporting portion 26 of the device -turning with the upper portion thereof until the anchors 28 catch on a shoulder or upset inside the drill pipe. This spring 40, therefore, serves the double purpose of holding the blades closed and making a friction hold on top of the swivel. This nut 41 is pinned to the s indle 42 so that the spring will not cause t is nut to turn when the top of the cutting mechansm is rotating and the bottoni is stationary or held by the projected wings or `stops 28.

As before stated, the head 23 is swiveled onto the rod 22, the slots 24 fitting over the blades at all times when the cutter is assembled.` In putting these parts together, the first operation is to slip the head 23 over the blades,` fitting the blades into the slots in the head, then the part 10 is screwed into the pipe section or cylindrical member 14. When 1() has been completely screwed into 14, the top of the head 23 is against `the shoulder on the bottom of the portion 10 and the lower end of the head is resting over the top of the blades which are completely hiddeninside the bottom of the head 1n their grooves.

If it be desired to cut a rotary drill pipe While it is in position in the hole being drilled and for the purpose stated, the cutter is lowered down inside of the stuck drill pipe by means heretofore described. lVhen the proper place has been reached where the cut is to be made, the cutter and the connections at the top of the hole are rotated rapidly to the right in Figure 5, causing the centrifugal action, aided by the mudlv within the hollow drilling tool, to force open the stops or dogs 28 and these stops, as the cut Y ter is forced downward, will catch on the next tool joint shoulder. When these stops catch, they hold the tubular member 14 against downward movement, permittin the square shank 22 to be lowered throug the collar 10, causing the .tapered head 23 to enga e the upper ends of the cutting blades, orcing them out against the inside of the drill pipe through the slots 14 as the weight of the pipe above and of weight 31 is allowed to come upon the cutters. Ever thing below the swivel 25 is, of course, he d stationary by the stops or dogs 28 while the cut is being made. After the cutter has been forced completely outward, the pipe connections to the equalizer weight 31 are forced, as heretofore described,'so that this head 35 is midway ofthe pipe section 33.

The pipe sections connected to 31 are then rotated which, of course, rotates the shank 22 toward the right, as before stated, and the blades cut through the drill pipe. When the drill pipe has been entirely cut through, the weight 31 is raised until it contacts with the shoulder 34, then upon a further pull upward, the head 23 is raised until it contacts with the shoulder formed by the lower end of the collar 10 and as soon as the head has been removed from between the upper ends of the cutter blades, the spring 21 will cause the cutter blades to close or contract into the tubular portion 14. If now the internal cutter be raised, the beveled` faces of the stops 28, when they engage with a tool joint and when the shank 22 is rotated to the left will cause t-he stops'to automatically close so that they may be drawn up through the tool joints or let back down to make a deeper cut in the hole.

A cutter constructed in this manner may also be used for cutting cemented casings above the cement, allowing the casings to be withdrawn after a producing well has ceased to produce. The cutter can also be enlarged and instead of providing the stops or dogs 28, drill pipe can be put on the bottom, said pipe having a length equal to the distance from the bottom of the casing up to where the cut is to be made and this will permit the cutter to operate in a well cas- 1ng just as it operates in a drill pipe, except for the means for su porting of the cutter. This makes a seat or the cutter instead of the stops 28.

As shown in Figure 4 and as before referred to, it is possible to have thegrooves 13 formed in the collar 10 and provide a transverse pin passing through the shank 22, which pin will enter these grooves and hold the shank 22 from rotation relative to the collar 10 and I, therefore, do not wish to be limited to a construction wherein a` square shank is used with a square collar, as any construction which will permit longitudlnal movement of the shank within the collar but unitary rotation of the shank and collar will be within my invention as defined in the appended claims.

the cutters havlng blades projectible through said slots, ahead carried by the shank and formed to wedge the upper ends of the cutters apart and force the blades out through said slots when the head and shank are lowered, and means for arresting the descent of the lower end of the pipe section, said means permitting a rotation of the shank and sald pipe section with the cutters.

2. An internal pipe cutter of the character described including a collar, a pipe section extending downward therefrom, cutters pivotally mounted within said pipe section and having their upper ends formed with outwardly defiected blades, the pipe section having slots through which said blades may be projected, means urging the cutters inward within the pipe section, and means disposed below the lower end of the pipe section which arrests its descent and with which the pipe section has swiveled engagement, a shank passing through said collar and held from rotation independently of the collar but being longitudinally movable with reference thereto, the shank having a head formed with upwardly and outwardly inclined grooves, the head being movable downward into engagement with the cutters to force the cutters laterally outward, the cutters engaging in said grooves.

3. An internal pipe cutter of the character described including a pipe section having slots, cutters mounted within the pipe section and projectible through said slots, means acting to retract the cutters, means .l for rotating the pipe section and projecting said cutters, means for arresting downward movement of the pipe section comprising a section having swiveled engagement with the pipe section and forming a continuation thereof, this section having a circumferential groove,l and arcuate anchoring wings pivotally mounted in 'the groove of said last section and adapted to be urged outward by centrifugal force when the pipev section is rotated in one direction, said wings being beveled upwardly.

4. An internal `pipe cutter of the character described comprising a pipe section having slots, cutters pivotally mounted within the pipe section and projectible through said slots, means for rotating said pipe section and for forcing the cutters outward, means for anchoring the lower end of the pipe section against downward movement, said means comprising a member swiveled to the pipe sectlon, and anchoring wings pivotally mounted upon said member and shiftable loutward when the pipe section is rotated in one direction but retracted when the vpipe section is rotated in the other direction.

5. An internal pipe cutter of the character described comprising a pipe section having slots, cutting blades pivotally mounted within the pipe section and rojectible throu h said slots, means including a depressi le member for forcing the cutters outward, said depressible member engaged with the pipe section against independent rotative 'movement, projectible means for holding the lower end of the pipe section against downward movement, and a connection between said depressible member and .the superposed string of pipe sections affordlng means whereby the weight of the superposed sections may be allowed to rest entirely upon the cutters to force them into projected position or raised therefrom and whereby the pipe cutting mechanism may be rotated. 6. A pipe cutting mechanism including a pipe section having slots, cutting blades pivotally mounted within the pipe section and projectible through said slots, a head having inclined slots and having a shank formed-to have sliding engagement with the pipe section but held against rotation independently thereof, said head being adapted to be forced downward into engagement with the cutting blades to force the cutting blades outward when the lower end of the pipe section is held against downward movement, means for raisin and lowering the cutting mechanism including a tubular member operatively connected to the depressible cutter operating member, said tubular member having a shoulder at its upper end, and an equalizing weight having limited sliding movement in the tubular member and rotative engagement therewith and adapted to be connected at its upper end to a string of supportingxpipe sections whereby the equalizing weig t, the depressible member and the cuttlng mechanism may be raisedvor lowered and rotated. 7 An internal pipe cutter of the character described comprising a pipe section having slots, cutting blades pivotally mounted within the pipe section and projectible through said slots, the lower' ends of the cutting blades having angular end faces extending in o posite directlons, an anchor carrying mem er swiveled to the lower end of the pipe section and having projectible stops shftable outward when sa1d member is rotated in one direction but retracted when the member is rotated in the other direction said member having a stem screw-threaded at its upper end, a collar connected to the first named pipe section and through which said stem passes, a nut engaging the stem, a washer mounted on the stem for rotation therewith, the nut being pinned to the stern, a vertically disposed compression spring resting upon said nut, and a conical cap mounted upon the up er end of the spring and bearing against t e angular end faces of the blades to urge said blades to a closed position, the spring creating friction against the stem to thereb;I resist rotative movement of said stop carrylng member.

In testimony whereof I hereunto ax my signature.

GEORGE V. POWERS. 

